1. Field of the Invention
The present invention relates to a structural arrangement for wireless communication terminals.
2. Description of the Prior Art
The current trend is to produce compact wireless communication terminals with functional and user friendly ergonomic features. A wireless communication terminal comprises a case in which are accommodated equipment units, in particular a radio transceiver unit comprising an antenna and a man-machine interface unit generally including a keypad, a screen and a sound transducer.
The search for improved convenience and ergonomics has led to housing the antenna inside the case, for example, through the development of patch planar antennas. The same trend is encouraging the provision of increasingly comprehensive man-machine interfaces of increasingly large size.
FIG. 1 shows diagrammatically the components of a wireless communication terminal, which generally comprises an insulative or partly metal rigid material case 10 containing components connected to a printed circuit 100. The terminal has a screen 20, a keypad 25, a battery 27, a wireless communication antenna 40, and a sound reproduction transducer 30 adapted to convert electrical signals that are fed to it into sound waves.
The sound transducer 30 can have several functions, such as those of an earpiece, a loudspeaker and a ringer. The earpiece is essentially intended to be placed against the ear of a user when using the device in a call, the ringer alerts the user to an incoming call or some other event, and the loudspeaker reproduces sound at a high volume, for example for hands-free use. To reproduce sound waves, the sound transducer 30 uses two separate volumes defining a front acoustic cavity 31 and a rear acoustic cavity 32 whose shapes and dimensions are chosen to achieve sound reproduction of sufficient quality for the application for which the transducer is intended.
In theory, the earpiece function requires a smaller component size than is required for a loudspeaker and ringer, which must emit a greater sound volume. The volume occupied by the sound transducer 30 can therefore not be reduced beyond a limit imposed by the loudspeaker function.
As previously mentioned, the current trend is to enlarge the man-machine interface, and in particular the screen, for example by using liquid crystal screens. Because the size of the keypad cannot be reduced, again for reasons of convenience in use, the present invention proposes to exploit the space occupied by the sound transducer to enlarge the space available to receive a screen, without commensurately decreasing the size of the keypad or increasing the size of the mobile terminal.
To this end, the invention proposes to retain only a simple earpiece on the front face of the terminal and to transfer the loudspeaker and the ringer function to the rear of the terminal, using the volume of the antenna as the front acoustic cavity.